Switch



Sept. 24, 1940.

J. w. HAMILTON ET AL 2,215,788

SWITCH Filed June 9, 1938 2 Sheets-Sheet l F 1 Z. 55 R5 55 JOE /L JOHNK. ASDER BY ZZ ATTORNEYS Sept. 24, 1940. J. w. HAMILTON ET A1. 2,215,733

SWITCH Filed June 9, 1938 2 Sheets-Sheet 2 INVENTORS J05 WHAM/L TONJgH/v K. ASDER 36 ATTORNEYS Patented Sept. 24, 1940- UNITED STATESPATENT OFFICE I 2,215,788 swrrcn Joe W. Hamilton and John K. Asder, LosAngeles, Calif.

' This invention relates to a delayed action switchand refers moreparticularly to a time delay action electric switch suitable for lightand other circuits.

This type of switch allows a person to manually actuate the switch, forexample, to extinguish lights, but these will remain illuminated for, av

predetermined time period to enable the user to leave the premises whilethe lights are still on.

Switches of this type employ a thermostat of bi-metallic type having aheating coil which is usually in shunt with the main circuit; however,when the switch is thrown manually to the oil position, the circuit ofthe heating coil is placed in series with the load, so that the coiloperates as a part of the current path through the load circuit. Thisarrangement has the drawback-that when the load is changed, the totalresistance changes. If the load resistance is reduced materially, thecurrent flow rises proportionately. And if this practice is carried toofar, the heating coil will usually burn out, or not be heated at all.Consequently, switches of this character are limited to their specificloads. For

example, practical experiments have shown that a'switch designed to givea two-minute delay a with a 40-watt load would have approximately aone-minute delay with a Gil-watt load, a halfminute delay-with 75 watts,and proportionally less time as the load increased until at about 250watts the heating coil of the switch would burn in two. I

An object of the present invention is the provision of a delayed actionswitch which will operate uniformly and without any variations in thetime period of the delayed action irrespective of the magnitude of theload in the main circuit.

Another object is the provision of a delayed action switch capable ofcarrying anyload which its main line contacts can carry.

Other objects of the present invention will be apparent in the course ofthe following specifica- .tion.

The objects of the present invention may be realized by arranging theheating element of the thermostat in a multiple circuit relationshipwith the load, so that the heating element can work concurrently withbut independently of the load. The heating element is, therefore, soconstruct .ed that it canbe placed across thesupply line independentlyof any other device or circuit.

The invention wilLappear' more clearly from the following detaileddescription when taken in connection with the accompanying drawings,

showing by way of example a preferred embodiment of the inventive idea.

In the drawings:

Figure 1 shows in rear elevation a switch constructed in accordance withthe principles of the 5 present invention;

Figure 2 is a section along the line 2-2 of Figure 1;

Figure 3 is a section along the line 3-4 of Figure I; 10

Figure 4 is a perspective view of the switch in its of! position;

Figure 5 is a diagram showing the electrical connections of the switchin the 012 position;

Figure 6 is similar to Figure 4 and shows the II switch in its onposition;

Figure 7 is a section similar to 'Fig. 2 and shows the switch in its onposition;

Figure 8 is a diagram similar to that of Figure 5 and shows the circuitin the on position of the :0 switch;

Figure 9 is similar to Figures 4 and 6 and shows the switch in itsintermediate position with the heating coil of the thermostat includedin its circuit; 1 25 Figure 10 is a section similar to Figs. 2 and '7and shows the switch in its intermediate position; and

Figure 11 is a diagram similar to those shown in Figures 5 and 8 andillustrates the circuits at a time when the heating coil of thethermostat is energized by the electrical current.

The switch shown in the drawings may be conveniently aflixed to a walland comprises a switch box or casing having a front wall l5, side wallsIt and H, the top l8 and the bottom or base l9. This switch box is madeof 'an insulating material such as Bakelite, porcelain or the like.

The front wall l5 has an opening 20 through i which the finger-operatedinsulating lever 2| extends. The lever 2| has an inner round portion 22which is rotatable along with its axis 23 mounted in the walls l6 andI1. vAn extension arm 24 is securely attached to the portion 22 of thefinger lever 2i and carries apivot pin 25. A fork 26 embraces the pivotpin 25 and is connected with one end of a coil spring 21, the oppositeend of which surrounds an innerprojection 28 of a yoke or swingingmember 28. 60

' The yoke or swinging member 29 is rotatable along with its axis IIIwhich extends through the side wall It and member 41 of the switch box.The yoke 29 comprises two side bars II and 32 which are interconnectedby a transverse bar or circuit-closer bar 33. This is the arrangementfor giving an automatic, quick movement to the frame or yoke 29 when thefinger-operated lever 2| is moved from the open circuit position or offposition, shown in Figures 1 to 5', to the on position or the closedcircuit position, shown in Figures 6 to 8.

An insulated wire 34 is connected with a plus terminal 35 carried by thetop l8 of the casing. The minus terminal is connected with the wire 35and is carried by the bottom |9 of the casing. The terminal 35constitutes an end element common to the two circuits 51 and 58 (Fig.5).

The terminal 35 is connected by means. of a wire 38 with the device 39,which is illustrated diagrammatically in the drawings and whichconstitutes the load of the main circuit; it may be a lamp or a seriesof lamps, a heating device, or any other consumer of electrical energy.Hereinafter it will be referred to as the lamp 39.

A wire 49 connects the lamp 39 with another terminal 4! situated uponthe top l8 of the casing. The terminal 4| is electrically connected witha strip 42 integral with the Ushaped contact 43, which is also aconductor of electricity. The contact 43 comprises an upwardly extendingportion 44 provided with a bent end 45, and constitutes an end 'elementof the load circuit. As shown in Figures 6 and 9, the bar 3| of theswinging yoke 29 is adapted to engage the portion 44 rangement, anelectrical connection is established between the yoke 29, and theL-shaped member 41, and the minus terminal 31.

A wire 48 is connected to the terminal bolt 49, constituting a part ofthe plus terminal 35. The opposite end of the wire 48 constitutes theheating coil 55 of the bimetallic strip 5|. The opposite end of theheating coil 55 is connected to the terminal 53 carried upon the top l8of the casing.

A tongue or contact 54, which is provided with a curved portion 55, issituated within the casing,

and is electrically connected with the terminal 53 (Figs. 2, 7 and 10).An' insulatingblock 55 is used to support the tongue 54 in its properposition within the casing. The member 54 constitutes an end element ofthe thermostat circult 58.

An electrical connection is maintained between the tongue or the strip54, which may be engaged by the transverse bar 33 of the swinging member29, and the heating coil 58, as well as the positive terminal 35 of theswitch. I

The lower portion of the bimetallic strip 5| is provided with aninsulating knob 51. which is adapted to engage the bent portion 58 of adouble-armed lever 59, when the strip 5| is bent due to heating. The endportion 55 of the lever 59 is reciprocablein the direction toward andaway from a block 5| constituting a part of the bottom l9 of the casing.A coil spring 52 engages the block 5|, while its opposite end surroundsthe portion 55 and presses against the bent porin its vertical position,which is shown in the drawings.

The vertical arm 55 of the lever 59 is provided with a hook or .detent55, which is adapted to engage the bar 32 of the swinging circuit closer29 in the course of the return movement of the circuit closer 29 to itsoff position.

The operation of the device is as follows:

In the off position shown in Figures 1 to 4 of the drawings, the switchlever 2| is directed upwardly while the swinging circuit closer 29 alsoextends upwardly but is inclined in the opposite direction. As shown inFigure 2, the tongue 54 is out of engagement with the circuit closer 29,which is also out of engagement with the U- shaped contact 43. As shownin the diagram of Figure 5, in this position the load circuit 51 and thethermostat circuit 53 both remain open.

In order to close the switch, the operator pulls the lever 2|downwardlyso that it assumes the position shown in Figures 6 and '1. Thelever turns along with its axis 23 and the rod 24 of the lever swingsupwardly along with the pivot and the fork 25, which is engaged by thespring 21. Due to the pressure of the spring 21, the circuit closer 29is rapidly swung in the opposite direction, with the result that thetransverse bar 33 of the circuit closer 29 is moved downwardly into theposition shown in Figures 6 and '1, in which his situated underneath thetongue 55. In the course of this swinging movement of the circuit closer29, the bar 32 slides along the inclined surface 59 of the hook 55,while the transverse bar'33 slides along the tongue 54. However, in theend position shown in Figures '6 and 7, the hook 55 is situated abovethe transverse bar 33 which is also out of engagement with the tongue54.

As shown in Figure 8, in this position of the switch a circuit isestablished between the positive terminal and the negative terminal 31.

The alternating electrical current will flow through he wire 34, theterminal 35, the lamp 39, the connecting piece 42, the U-shaped contact43, the circuit closer 29, the L-shaped member 41, the bolt 45, theterminal 31, and the wire 35. However, in this on position of theswitch, the thermostat is not included in an electrical circuit. g

If now the user desires to turn oi! the switch, he swings the lever 2|upwardly until it is moved into the position shown in Figures 9 and 10of the drawings. Due to the described connections, the circuit closer 29will also tend to swing upwardly and the transverse bar 33 will slidealong the lever 59 until it' is brought into engagement with the hookand is stoppedby that hook. This position.- is shown in Figures 9 and10. In this position the transverse bar 33 of the circuit closer 29 isin contact with the tongue 54. At the same time the side bar 3| oi the Ithe coil 55 will flow through the terminal 53 to the tongue 54, flowingfrom'the tongue 54 to the 1s circuit closer 29, the L-shaped member andthe negative terminal 31.

. allytoward the wall I! sliding upon the underlying portion of thecircuit closer 28 until finally the hook 66 will release the circuitcloser 29. Them-under the action of the spring 21, the circuit closerwill spring back from the position shown in Figures 9 and 10 to the offposition shown in Figures 1 and 2 of the drawings. The engagementbetween the circuit closer I! on the one hand and the tongue ii and theU-shaped contact 43 on the other hand will be interrupted, so that nocurrent will flow any more through the load circuit 61 or the thermostatcircuit 88.

The bimetallic strip 5| will gradually cool and return to its originalposition, which is shown in the drawings, while at the same time thespring 82 will cause the lever 58 to return to its illustrated position.

Practical experience has shown that the period of time during which thecurrent is caused to flow through the load circuit 61 after the lever-II has been switched to its off position, depends entirely on theconstruction of the switch and is unaffected by the size of the load 3!.

The switch may be so constructed that the circuit 61 is interrupted afew seconds to several minutes after the lever 2| has been switched011'.

One of the important advantages of the present construction is that thethermostatic circuit 68 is operated while the load circuit 61 is intact,so that there are two individual, distinct and complete circuits inoperation at one and the same time.

It is apparent that the specific illustration shown above has been givenby way of illustration and not by way. of limitation, and that thestructure above described is subject to wide variation and modificationwithout departing from the scope or intent of the invention. Forexample, the switch may have the form of a pedant switch or a socketswitch. All of such and other variations and modifications are to beincluded within the scope of the present invention.

What is claimed is:

1. In a switch, a terminal adapted to be connected to one pole of asource of electrical energy and to the main consumer of said electricalenergy, another terminal adapted to be connected to said consumer ofelectrical energy, a third terminal adapted to be connected to the otherpole. of said source of electrical energy, a circuit closer, aninsulated toggle-type device engaging said circuit closer for swingingit backwards and forwards from an open circuit position to a closedcircuit position and from the closed circuit position to the opencircuit poation, insulated restraining means positioned to arrest saidcircuit closer in the course of its movement from the closed circuitposition to the open circuit position in an intermediate position, aconducting member engaging said circuit closer in all positions of thelatter and permanently connected with the third-mentioned terminal, a

single contact connected with the'second-mentioned terminal andoperatively engaging said circuit closer in its closed circuit positionand inits intermediate position to maintain a flow of electrical energyfrom said source through said main consumer while the circuit closer isin the closed circuit position and while it is moved from the closedcircuit position to the intermediate position, a thermostat, meansconductively connecting said thermostat with the first-mentionedterminal, a single contact conductively connected with said thermostatand contacting said circuit closer in said intermediate position,wherebysaid thermostat is connected with said source in parallel to saidconsumer in said intermediate position, and means actuated by saidthermostat when the latter is heated by current of said source todisengage the restraining means and permit further movement of thecircuit closer from the intermediate position to the open circuitposition, the last-mentioned contact being formed to remain longer inengagement with the circuit-closer than the first-mentioned contact inthe course of the movement of the circuitcloser from the intermediateposition to the open circuit position, whereby the connection of saidthermostat with said source is interrupted after the interruption of theconnection of said consumer with said source.

2. In a switch, a terminal adapted to be connected to one pole of asource of electrical energy and to the main consumer of said electricalenergy, 1 another terminal adapted to be connected to said consumer ofelectrical energy, a third terminal adapted to be connected to the otherpole of said source of electrical energy, a conducting circuit-closingyoke having two sidebars, a transverse bar interconnecting saidsidebars, and an axis connected with at least one of said side-bars; aninsulated toggle-type device an open circuit position to aclosed'circuit position and from the closed circuit position to the opencircuit position, insulated restraining means positioned to engage oneof the side bars of the yoke in the course of the movement of the yokefrom the closed circuit position to the open circuit position andthereby arrest the yoke in an intermediate position, a conducting memberengaging the axis of said yoke in all positions of the latter andpermanently connected with the third-mentioned terminal, a singlecontact connected with the second-mentioned terminal and operativelyengaging another side bar of the yoke in the closed circuit position andthe intermediate position of the yoke to maintain a flow 0! electricalenergy from said source through said main consumer while the yoke is inthe closed circuit position and while it is moved from the closedcircuit poistion to the intermediate position, ing said thermostat withthe first mentioned terminal, a single contact conductively connectedwith said thermostat and-contacting the transverse bar of the yoke insaid intermediate position, whereby said thermostat is connected withsaid source in parallel to said consumer in said intermediate position,and means actuated by said thermostat when the latter is heated bycurrent of said source to disengage the restraining means and permitfurther movement of the yoke from the intermediate position to the opencircuit position,

3. In a switch, a terminal adapted to be cona thermostat, meansconductively connectpin embraced by said fork, a finger level connectedwith said pivot pin and movable to two diflerent positions to cause saidpivot pin, said fork and said coil spring to swing said circuit closerfrom an open circuit position to a closed circuit position and from theclosed circuit position to the open circuit position, insulatedrestraining means positionedto arrest said circuit closer in the courseof its movement from the closed circuit position to the open circuitposition in an'intermediate position, a conducting member engaging saidcircuit closer in all posi-- tions of the latter and permanentlyconnected with the third-mentioned terminal, a single contact connectedwith the second-mentioned terminal and operatively engaging saidcircuitcloser in its closed circuit position and in its intermedateposition to maintain a flow of electrical energy from said sourcethrough said main consumer while the circuit closer is in the closedcircuit position and while it is moved from the closed circuit positionto the intermediate position, a thermostat," means conductivelyconnecting said thermostat with the first-mentioned terminal, a singlecontact conductively connected with said thermostat and contacting saidcircuit closer in said intermediate position, whereby said thermostat isconnected with said source in parallel to said consumer in saidintermediate position, and means actuated by said thermostat when thelatter is heated by current of said source to disengage the restrainingmeans and permit further movement of the circuit closer irom theintermediate position to the open circuit position.

7 4. In a switch, a terminal adapted to be connected to one pole of asource of electrical energy and to the main consumer of said electricalenopen circuit position in an intermediate position,

a conducting member engaging said circuit closer in all positions of thelatter and permanently connected with the third-mentioned terminal, asingle contact connected with the second-mentioned terminal andoperatively engaging said circuit closer in its closed circuit positionand in its intermediate position to maintain a flow of electrical energyfrom said source through said main consumer while the circuit closer isin the closed circuit position and while it is moved from the closedcircuit position to the intermediate position, a bimetallic strip, aheating coil enclosing. said bimetallic strip and conductively connectedwith the first-mentioned terminal, a single contact conductivelyconnected with said heating coil and contacting said circuitcloser insaid intermediate position, whereby said heating coil is connected withsaid source in parallel to said consumer in said intermediate position,and insulated means movable by said bimetallic strip when the latter isheated by current of said source to swing said restraining lever andthereby permit further movement of the circuit closer from theintermediate position to the open circuit position.

JOE W. HAMILTON.

JOHN K. ASDER.

